The principle of the camera through the fog is in the visible light range, a certain frequency of light can penetrate the fog. However, due to the different wavelengths, the light is needed to focus by the camera and design is need to image this invisible light. Therefore, to achieve through the fog effect, the surveillance camera must meet the following requirements:
- Lens with chromatic aberration compensation.
- Near infrared high sensitivity CCD.
- The black level stretching image processing.